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| /*********************************************************************************
| * Copyright: (C) 2025 LingYun IoT System Studio
| * All rights reserved.
| *
| * Filename: mmap_ipc.c
| * Description: This file is Memory Map(IPC) example program.
| *
| * Version: 1.0.0(11/10/2025)
| * Author: Guo Wenxue <guowenxue@gmail.com>
| * ChangeLog: 1, Release initial version on "11/10/2025 01:02:05 PM"
| *
| ********************************************************************************/
| #include <stdio.h>
| #include <stdlib.h>
| #include <sys/mman.h>
| #include <unistd.h>
| #include <string.h>
|
| int main(void)
| {
| char *shm = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
| if (shm == MAP_FAILED)
| {
| perror("mmap");
| exit(1);
| }
|
| pid_t pid = fork();
| if (pid == 0)
| {
| /* 子进程 */
| strcpy(shm, "Message from child process");
| }
| else
| {
| /* 父进程 */
| sleep(1);
| printf("Parent read: %s\n", shm);
| }
|
| munmap(shm, 4096);
| return 0;
| }
|
|
